android - AlarmManager 触发后如何调用 AlarmManager 方法？

Question

我想在每次触发 AlarmManager 时额外更改 Intent。这可能吗，我如何在 AlarmManager 触发后立即调用它？

代码:

public void startCollector(){
    final int LOOP_REQUEST_CODE = 4;
    Intent i = new Intent(getApplicationContext(), DataCollector.class);
    PendingIntent sender = PendingIntent.getBroadcast(getApplicationContext(),LOOP_REQUEST_CODE,i,PendingIntent.FLAG_NO_CREATE);
    long firstTime = SystemClock.elapsedRealtime();
    firstTime += 3*1000;
    AlarmManager am = (AlarmManager)getSystemService(ALARM_SERVICE);
    //TO CHANGE INTENT EXTRAS DO NOT REMOVE.
    if(sender != null){
        am.cancel(sender);
    }
    if(getLocation() != null) {
        i.putExtra("JLocation", getLocation());
    }
    i.putExtra("JLocation",getLocation());
    sender = PendingIntent.getBroadcast(getApplicationContext(),LOOP_REQUEST_CODE,i,PendingIntent.FLAG_CANCEL_CURRENT);
    am.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP, firstTime, 100000, sender);
}

Answer 1

我建议您使用精确的警报而不是使用 setRepeating() 并在每次触发时重新安排。

(setRepeating() 是不准确的，无论如何都不适用于 Doze)

例如:

Intent intent = new Intent(this, AlarmReceiver.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, intent, 0);

AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);

// if you would like to fire the next alarm very precisely
// put this value in the Intent and use it in your receiver
// to calculate the next time for the alarm
long fireAt = SystemClock.elapsedRealtime() + 5000;

if(Build.VERSION.SDK_INT >= 23) {
    am.setExactAndAllowWhileIdle(AlarmManager.ELAPSED_REALTIME_WAKEUP,
                fireAt, pendingIntent);
} else if(Build.VERSION.SDK_INT >= 19) {
    am.setExact(AlarmManager.ELAPSED_REALTIME_WAKEUP, fireAt, pendingIntent);
} else {
    am.set(AlarmManager.ELAPSED_REALTIME_WAKEUP, fireAt, pendingIntent);
}

在你的接收器中:

@Override
public void onReceive(Context context, Intent intent) {

    // change the Intent as you wish
    intent.putExtra("anExtra", "aValue");
    // or create a new one
    //Intent newIntent = new Intent(context, this.getClass());

    PendingIntent pendingIntent = PendingIntent
        .getBroadcast(context, 0, intent, 0);

    AlarmManager am = (AlarmManager) context.getSystemService(ALARM_SERVICE);

    long fireAt = SystemClock.elapsedRealtime() + 5000;

    if(Build.VERSION.SDK_INT >= 23) {
        am.setExactAndAllowWhileIdle(AlarmManager.ELAPSED_REALTIME_WAKEUP,
                fireAt, pendingIntent);
    } else if(Build.VERSION.SDK_INT >= 19) {
        am.setExact(AlarmManager.ELAPSED_REALTIME_WAKEUP, fireAt, pendingIntent);
    } else {
        am.set(AlarmManager.ELAPSED_REALTIME_WAKEUP, fireAt, pendingIntent);
    }
}